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Internet Message Format  |  1992-08-25  |  1018 b 
  1. Path: sparky!uunet!usc!news!nic.cerf.net!jcbhrb
  2. From: jcbhrb@nic.cerf.net (Jacob Hirbawi)
  3. Newsgroups: sci.physics
  4. Subject: RE: Satellite spying
  5. Message-ID: <2599@news.cerf.net>
  6. Date: 25 Aug 92 23:05:47 GMT
  7. Sender: news@news.cerf.net
  8. Organization: CERFnet
  9. Lines: 19
  10. Nntp-Posting-Host: nic.cerf.net
  11.  
  12. In article <17chpmINNma3@agate.berkeley.edu> 
  13. ted@physics3 (Emory F. Bunn) writes:
  14.  
  15. > But the really fishy thing is that it's better than the resolution that
  16. > Hubble was supposed to get.  The Hubble was supposed
  17. > to be near the theoretical diffraction limit for resolution, which 
  18. > would be about
  19. > wavelength / diameter = 6 x 10^-7 meters / 1.5 meters = 
  20.                           ^^^^^^^^^^^^^^^^
  21. >     4 x 10-7 radians = 0.08 arc-seconds.
  22.  
  23. Perhaps they're using a different wavelength !
  24.  
  25. After all do you really need 6 x 10^-7 meters to get a resolution
  26. of a few centimeters. The human eye does not give the best example
  27. of wavelength used versus required resolution. Just guessing.
  28.  
  29. Jacob Hirbawi
  30. JcbHrb@CERF.net
  31.